One thing to note is that while Hynix's have numerous patents related to phase change memory they have only one ReRAM/memristor patent (for an application in RFID). Thus all else being equal there is more economic incentive for Hynix to develop phase change memory. Below is a link to comparative US patent data for companies invested in memory resistors vs. phase change memory.
http://memresistor.wordpress.com/article/business-landscape-for-memresistor-electronics/

The way SK Hynix approaches these memories, by sharing risk with big names like Toshiba for STT-MRAM, HP for memristor and IBM for phase change memory, indicates they are not really into using these in the near future. So it's funny to watch the big-name partner get all excited and make optimistic projections.